Polders — Normandy

A polder is an artificial stretch of land gained over water, most often below sea level, from marshes, estuaries, lakes or coastal areas. The surface to be built is first surrounded by dikes. The water trapped in this perimeter is then captured by a set of pumps once operated by windmills and, today, by electric pumps. The drainage of the land is facilitated by a network of stretchers and basins. Even after the polder has dried up, the pumps continue to remove the excess water that would leak into the polder. There are also river polders, natural expanses in the flooding zone of a river, arranged in polder by a drainage system.